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	<title>通过阴影来弱化背景</title>
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	.overlay {
		position: fixed;
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	.lightbox {
		width: 200px;
		height: 100px;
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		transform: translate(-50%, -50%);
		background: #fff;
		position: absolute;
		z-index: 1;
		padding: 20px;
		/*box-shadow: 0 0 0 50vmax rgba(0,0,0,.8); box-shadow方案*/
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<body>
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		A few days before his death, Tyler beckoned me over to his hospital bed and whispered
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